Microchannel fabrication in PMMA based on localized heating by nanojoule high repetition rate femtosecond pulses.

Microchannels are fabricated in a poly(methyl methacrylate) substrate by high repetition rate, nanojoule femtosecond laser pulses. The mechanism for channel fabrication is based on the localized heating of the substrate due to the high repetition rate of the laser, resulting in smooth walled cylindrical channels. Microchannels with diameters of 8 - 20 microm can be fabricated at 800 microm/s using 80 fs pulses at a repetition rate of 80 MHz and energy of 0.9 nJ/pulse.